Turn on lexical-binding in some net libs

Turn on lexical-binding in some net libs

* lisp/net/dbus.el: Turn on lexical-binding.
(dbus-list-hash-table, dbus-list-known-names):
(dbus-introspect-get-node-names, dbus-introspect-get-interface-names):
(dbus-introspect-get-method-names, dbus-introspect-get-signal-names):
(dbus-introspect-get-property-names):
(dbus-introspect-get-argument-names, dbus-get-all-properties):
(dbus-property-handler, dbus-get-all-managed-objects):
(dbus-managed-object-handler): Replace add-to-list with push. Add
nreverse in some places where the APPEND argument of add-to-list was
used.
* lisp/net/network-stream.el: Turn on lexical-binding.
* lisp/net/newsticker.el: Turn on lexical-binding.
* lisp/net/shr.el: Turn on lexical-binding.
(shr-make-placeholder-image): Remove unused variable binding.
(shr-inspect-table): Replace ignored bindings with underscore.